1958-06-16: Convair CV-440 Metropolitan (PP-CEP) — Cruzeiro do Sul — Curitiba, Brazil

21 fatalitiesCuritiba, BrazilLanding (descent or approach)

An aircraft crashed while performing an intermediate approach near Florianópolis after encountering severe weather conditions.

What happened

While traveling from Florianópolis, the aircraft was directed by air traffic control to begin its approach procedure for Runway 33 near the NDB CT station. The pilot commenced the intermediate approach leg as instructed. Approximately three minutes later, after the flight had failed to report reaching the base turn, tower controllers attempted to contact the pilot to verify the aircraft's position. No response was received, leading the tower operator to issue an alarm due to the loss of two-way radio communication.

It was subsequently confirmed that the aircraft had crashed. The accident resulted in 21 fatalities (comprising five crew members and 16 passengers) and left 5 passengers seriously injured. The impact resulted in the total destruction of the aircraft.

Findings

Investigations conducted by the Aircraft Accident Investigation Commission revealed that during the final stages of the intermediate approach, the base turn, and the start of the final approach, the aircraft was flying through cumulonimbus clouds. The investigation concluded that strong downward currents impacted the aircraft's rate of descent, causing it to lose sufficient altitude to strike the ground.

Probable cause

Severe downdrafts within cumulonimbus clouds caused the aircraft to lose altitude during its approach.